New on LowEndTalk? Please Register and read our Community Rules.
All new Registrations are manually reviewed and approved, so a short delay after registration may occur before your account becomes active.
All new Registrations are manually reviewed and approved, so a short delay after registration may occur before your account becomes active.
SSD optimisation
SolidxGaming
Member
in General
Just being curious and in a bid to fix my problem, I want to ask, what do hosting companies like @buyVM etc do to optimise SSD performance. I bought a server from hetzner this month for my VMs and suddenly saw on a VM very low IO speeds (50-60 Mbit/s) and everything was idle. Just the VM's OS was running (verified that with iotop). before telling hetzner to replace the drive (I don;t see anything abnormal in the smartctl though), i wanted to know this.
Comments
And I have this disks: SAMSUNG MZ7LN512HMJP
Well usually they are in RAID 10 but you should definitely be getting higher speed than 50 (MB/s?).
Hardware RAID?
Oh, mine is in RAID 1, and software raid.
Are they running with 6Gbit/s at the moment ?
Isn't your Software raid initialising for some reason now ?
If you measure disk IO speed in Mbit/s, there's not much anyone here can do to help you, consider hiring an admin or using managed services.
Look up the effect overprovisioning (or lack thereof) has on SSD write performance.
Really sorry, autocorrect. I meant 50-60 MBps. And yes they are running at 6 Gbit/s. I did like 20 tests and it randomly went from being 400 MB/s to 56MB/s.
400 or 40?
Max reached was 400, and lowest was 56. That's how it is jumping. Seems to be stable now though.
http://i.imgur.com/4d0RX4r.png
Your screenshot doesn't look bad for SW Raid 1
Check with your provider. May be they were running backup.I didn't realize you talking about dedi.
What virtualization do you use? If you use proxmox, try to use virtio for the disk
Seems to be okey. If you have SSD dives, you may use ZFS for SSD caching.
Have you ever tried to use ZFS on a software RAID on a system with low RAM? This isn't a great idea on anything with less than 16GB RAM due to the way ZFS is constructed.
Thanks for your comments.
@akhfa I am already using virtio for the disks.
@SPUZE Thanks will look into it.
@WSS I have 32 GB RAM
Of course i have tried and used ZFS on a software RAID1 system with 16GB RAM. ZFS uses about 4GB plus 1GB RAM for each TB RAW disk space.
That it does. Plenty of folks throw out the "Oh just use ZFS" without realizing the overhead. Most folks would actually be perfectly fine with ext4- but I love me some ZFS.
I had exactly the same issue that you are facing with online.net in 1 server. If I run dd continuously, the speed would gradually decrease. After spending a lot of time to examine, I found that the disk SMART is not working properly and I ask Online to replace these disks. Now it's running fine.
It is definitely not working properly.
233 Media_Wearout_Indicator 0x0013 099 099 000 Pre-fail Always - 16735271Should have been 100 or so. I don't know why this is so high.
So I think you should ask for a replacement. Hetzner supports are very nice.